You have to decide the location and the amount of power before launching your comet. When you release your comet, it will start moving around depending on the gravitational forces of the planets. The comet tends to get close to a planet due to the pulling force.

You have to make sure that the comet doesn't crash into any planet before the blue bar at the bottom disappears. This game requires a lot of patients, skill and luck.

Hold Down the Left Mouse Button to place your comet and then Drag the Mouse in the opposite direction to set the power and finally Release the Mouse Button to launch the comet.